Combined flashlight and circuit tester



July 26, 1938.

E. o. SCHEERER COMBINED FLASHLIQHT AND CIRCUIT TESTER Filed May 18, 1935Patented July 26, 1938 PATENT OFFICE COMBINED FLASHLIGHT AND CIRCUITTEST Ernest Otto Scheerer, Linden, N. J. Application May 18, 1935,SerialNo. 22,278 6 Claims. ((ll.'175-?183) This invention relates to animproved device fortesting electrical-circuits, and one of its ob-'jects is to provide an attachment for flashlight cases, which can beoperated to test the condition of an electrical circuit, the flashlightlamp serving as anindicator for showing the action of the currentproduced by the battery in flowing through the circuit.

Another object of the invention is the provision of an attachment forflashlight cases, which includes a windable conductor wire, and meanswhereby this wire can be extended from the end of the flashlight caseand be connected to one terminal or portion of an electrical circuit,and the current of the flashlight battery used to operate the'circuit,if it is active, and the condition of the circuit observed through theoperation of the flashlight bulb or lamp. Another object of theinvention is the provision of an attachment for flashlight cases,including a self winding conductor wire or element, one end of which iselectrically connected to one end of the flashlight battery, and theother endoi which is equipped with a metal connector or clip alsonormally connected electrically tothe flashlight case, but detachabletherefrom to permit of distant connection to a portion of a circuit tobe tested, whereby the dry cells of the flashlight case may be used, incombination with the self winding conductor to make working tests ofmotors, bells, lighting circuits, etc;

A still further object of the invention is the provision of anattachment of this kind, with means for operating a telephonic receiverfrom the dry cells, so that sensitive'workingtests may be made underconditions, ofiering higher. circuit resistance, which would not be veryresponsive to the flashlight bulb.

Another object of the invention is the provision of a combinedflashlight and testing device, which will permit of the free use of theflashlight for all desired purposes, and permit of the use of the drycells of the flashlight to test electrical circuits, either by using theflashlight lamp alone, or in conjunction with the telephonic receiver toshow the activity or inactivity of the circuit subjected to test.

With the above and other objects in view the invention consists incertain new and useful combinations, constructions, and arrangements ofparts, clearly described in the following specification, and fullyillustrated in the accompanying drawing, in which:

Fig. 1 is a side view of the improved device.

Fig. 2 is a longitudinal sectional view, through the rear end of thetesting device.

Fig. 3 is a transverse sectional view, taken on line 3-3 of Fig. 1,looking in the direction of the arrows.

Fig. 4 is a cross-sectional view, taken on line arrows. 1 Fig. 5 is adetail showing the'relationship of 4-4 of Fig'. .1, looking in thedirection of the the terminals of the cup. Fig. 6 is a detail showingthe bulb endof the device.

Referring to the drawing 5 designates the cylindrical metal'shell of theflashlight case, on the forward end of which the reflector 6 is screwthreaded or otherwise coupled. The usual incandescent lamp 1 isdetachably threaded in this trical contact with the metal case or shell5; and

its central electrode 8 may beelectrically conto engage the screwthreads ll. This metalcase or cap 12 is equipped with a central flxedguide I 3, formed of fibre or other suitable insulating material, inwhich the metal pin II is arranged to slide. This. guide or post carriesthe metal spring E5, the inner end of which is extended through the wallof the tubular guide H .to have electrical contact with the metal pinII. A coil spring I6 is arranged on this pin,

case, so that its usualmetal shell will have elecone end of whichengages the inner end of the guide l3, and the other end of whichengages the head ll formed on the inner end of the pin. This headprojects through a central opening formed in the flbre or insulating cupl8, so that electrical contact may be established with'the rear end ofthe adjacent dry cell.

A winding reel or spool i9 is arranged over the winding spring l5 and isconnected to the outer end thereof. On this reel or. spool the flexiblewire or conductor 2|! is wound, the inner end of this wire beingconnected to the spring l5 to conduct electricity from the dry cells,through the pin, and the spring, to the spring or other metal clip 2|,attached to the end of the wire 20. This wire is covered with rubber orother thin insulation, so that when the wire is pulled through the hole22 in the case l2 the metal terminal clip or connector 2! will not be incircuit with the case l2.

The case I2 is equipped witha binding post 23, located adjacent to thehole 22. When the clip is pulled away from the flashlight case andplaced in metallic contact with a portion of any electrical circuit, thebinding post 23 may be connected to another portion or terminal of thecircuit to be tested. With the manual switch of the flashlight oase inclosed position, current will flow from the dry cells through theflexible wire, to the clip 2|, through the circuit to be tested, if thesame is active or not broken, to the. post 23, to the case i2, to thecase 5, to the lamp 1, back to the dry cells.

In this circuit arrangement the lamp 1 will be r illuminated when thecircuit tested is found alive. -When the circuit to be tested has a highresistance, an ear piece or telephonic receiver 24 may be used. This earpiece may be connected to the case l2'by means of the ring frame 25,- insuch manner that it can be detached from the case II, or swung outwardlythereof. This 'ear piece is provided with a binding post '26 which is incircuit with one end of the enclosed wind-- ing of the receiver magnet,and is also provided with another binding post 21 which is in circuitwith the other end 01' the receiver winding.

When the clip 2| is in metallic contacting engagement with the case l2,the'flashlight may be employed in the ordinary manner.

The ring frame 25 provides ground electrical connection between thereceiver or ear piece and the case II, when the receiver is attached tothe case l2.

The combined device is particularly useful for electricians andmechanics, who must inspect electrical circuits indifferent buildingsand places, and who cannot carry around costly and heavy equipment forthis purpose. The equipment is designed to provide a compact unit, whichwill serve to illuminate a field of work, or to test any circuit, eitherby using the lamp of the flashlight as an indicator, or by using themore sensitive telephonic ear piece or receiver.

The testing unit is so constructed that it may be mounted in place ofthe usual closure cap on the end of the flashlight case or barrel. Itdoes not interfere with the operation of the flashlight, and providesmeans for making contact with portions of a circuit which are ,widelyseparated.

In Fig.- 5 I show an electrical lamp, consisting of an inner glass bulb40, which is equipped with an incandescent filament II, and the usualterminal electrical connector cap 42 and the central electrode 43. Anadditional bulb I4 is arranged around the bulb l0, and sealed atitspoint of connection therewith at 45 to provide a space 46 between thetwo bulbs, which is exhausted to provide a vacuum between the two bulbs.This results in. reducing the radiation losses of heat from theilluminating filament I, so that with less consumption of current thefilament can be properly energized to give maximum illumination, or withthe same current supply increased illumination will be obtained. Theeifect of this conservation of the heat energy produced by the .flow ofthe current, is to increase the life and efliciency of the dry batteryused for operating the improved bulb.

Having described my-invention I claim: I 1. The, combination with aflashlight having a case, a lamp on one end of the'case, dry'cel'lswithin the case, a metal cap mounted on the end of thecase, meanscarried by the cap to establish electrical connection with the drycells, a selfwinding drum arranged in the cap, a flexible electricalconductor connected to the drum, a

clip on the-end of the flexible conductor, ,said

.drum-and the conductor being electrically connected to the means, and aswitch for controlwhereby the electrical conductor may be employed formaking tests of circuits portions of which are widely separated fromeach other.

2. A device of the character described adapted for use with a handelectricalflashlighthaving a casing and a lamp at one end of said'casingand dry batteries within the casing electrically connected to the lampcomprising in combination a cap detachable on the end of the case andprovided with a spring pressed contact member engaging the dry celladjacent thereto, a spring rotated winding drum having electricalconnection with the spring pressed contact member, a flexible insulatedconductor connected electrically to the drum and windable thereon, aterminal connector connected electrically to the conductor and adaptedto be electrically connected with the cap when disposed against thesame, and means for controlling the circuit through the lamp.

3. A hand electrical testing attachment for hand electrical flashlightcases, consisting of a metal case adapted to be coupled to the end of astandard flashlight case and provided with a spring pressed electricalcontact member engageable with the adjacent dry cell of the flashlightcase, a ring frame having electrical connection with the metal case, atelephonic receiver mounted on the ring frame for detachment from themetal case, and means for making connection between the telephonicreceiver and. the flashlight case, whereby the receiver may be placed inelectrical circuit with the flashlight and operated by the batteriesthereof.

.4. An attachment for flashlights consisting of a casehaving acoupling'element to engage a flashlight case, a spring rotated drumwithin the first case, a flexible conductor cord connected with the drumand having a connecting element secured to one end thereof adapted to benormally held against said first case to permit of the ready extensionof said conductor, means for supplying current from a dry battery of aflashlight case connected with the first case to said conductor, meansfor establishingelectrical contact between said first case and saidflashlight case and an audible signal elementpivotally mounted on saidfirst case and having terminal connections to permit circuit connectionbeing established with the battery of the first case.

5. A device of the character described adapted for use with afiashlightcontaining a casing, \batteries and a bulb comprising in combination acap of a diameter and shape to fit upon the end of the flashlight as acap and having means for physical attachment to said cap, a contactwithin said cap adapted to engage one terminalof the battery, a springreel mounted co-axially with said cap, a conductor mounted on said reeland in rotatable contact with said contact, said conductorv extendingthrough an opening in said cap to the exterior and being provided with aterminal and a second terminal carried by said cap connected to saidcasing. h

6. A device in accordance with claim 5 and provided with a telephonereceiver mounted on said cap having one end of its magnet connected tothe terminal of the battery to which said flexible conductor is notconnected and having its other end'provided with a terminal exterior 'tothe-cap. Y a

- ERNEST SCHEERER.

